The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Many DC-to-DC converters require relatively large amounts of input current at startup (i.e., when power is initially applied). A power source supplying input power to the converter, however, may be current-limited or may have poor load regulation. Accordingly, the input voltage supplied by the power source to the converter may be pulled down when relatively large amounts of input current is required at startup.
A soft-start function minimizes the large input current at startup by gradually increasing current limit at startup, slowing a rate of rise of the output voltage of the converter, and reducing peak current required at startup. This prevents the input voltage of the converter from dropping when the power source is connected to the converter at startup.